This invention relates to wrap-around article carriers, sleeves and sleeve blanks.
Wrap-around article carriers are used to enclose a plurality of similarly shaped articles, such as beverage containers. Typically, such an article carrier comprises a sleeve with at least partially open ends. The sleeve is formed by folding a blank comprising a plurality of panels which become the top, bottom and sides of the sleeve. Usually, such a blank will have a generally rectangular shape with end portions of the blank interlocking to form a continuous sleeve for enclosing articles. The blank is constructed from a material that is suitable for folding while possessing sufficient rigidity and strength for use in an article carrier. Paperboard is a common material used in manufacture of article carrier sleeves.
Article carrier sleeves of the kind described above may be rapidly assembled to enclose articles by using machinery designed to form a sleeve from a blank. Such machinery folds the blank into a sleeve surrounding the articles and engages cooperating locks of the blank to maintain the sleeve in an erect state around the articles.
Having at least partially open ends of the sleeve reduces the amount of material required in constructing the article carrier and the number of steps required to form the carrier. However, the absence of material at the ends of the sleeve makes it possible for articles retained within the sleeve to move outwards through the end of the sleeve, possibly falling out, unless some feature is provided for limiting such outward movement. Outward movement of articles retained within the sleeve is a particular problem where the configuration of the articles at the top of the sleeve is different from that at the bottom of the sleeve, such as where the articles are bottles having a narrow neck portion, and a broader curved base portion.
Previous approaches to addressing the above problem include U.S. Pat. No. 5,094,347 issued to Schuster ('347 Schuster), U.S. Pat. No. 5,107,986 issued to Cooper ('986 Cooper). and U.S. Pat. No. 5,390,848 issued to Gungner et al. ('848 Gungner et al.). '347 Schuster, '986 Cooper, and '848 Gungner et al. provide integral article retaining features within the sleeve which are essentially three-dimensional protuberances formed in the bottom of the sleeve adjacent open ends of the sleeve. However, in each case, the machinery used for forming the sleeve must include a movable punch or rod element that forces a retainer flap through a corresponding opening in the inner bottom panel.
In other known sleeve designs, it is not necessary to have movable punch or rod elements in order to form a sleeve. Examples of such sleeves are those provided under the trademark JAK-ET-PAK, as described in U.S. Pat. No. 4,708,284 issued to Sutherland et al. ('284 Sutherland et al.). In '284 Sutherland et al., during formation of the sleeve, a male tab is first folded and then is pushed, by a ramp over which a part of the blank travels, through a corresponding opening (such as a slit) in an inner overlapping portion of the bottom panel of the sleeve so that the male tab extends within the sleeve and is engaged therein. The male tab serves as a secondary locking element for the sleeve and the tab may be positioned within the sleeve so as to separate adjacent articles held within the sleeve. While the kind of automated packaging machinery used to form the sleeve in '284 Sutherland et al. does not require a punch or rod element to push the male tab through the corresponding opening, the '284 Sutherland et al. design lacks the three-dimensional nature of the protuberances found in '347 Schuster, '986 Cooper, and '848 Gungner et al.
Another known design in which it is not necessary to have movable punch or rod elements in the machinery forming the sleeve, but which does provide a three-dimensional protuberance, is disclosed in U.S. Pat. No. 5,437,363 issued to Gungner ('363 Gungner). By forming a three-dimensional protuberance from a retainer flap using a male supporting tab, '363 Gungner is intended to provide the article retaining features of '347 Schuster, '986 Cooper, and '848 Gungner et al., while maintaining simplicity in formation associated with the sleeve in '284 Sutherland et al. However, the sleeve in '363 Gungner suffers from the drawback that the structural integrity of the three-dimensional protuberance may be compromised. What is needed is an improved design for an article retaining sleeve that addresses this drawback.